Not Applicable.
Not Applicable.
1. Field of the Invention
This invention relates to disk drive suspensions, and more particularly to improvements in wireless-type disk drive suspensions. The invention adds a secondary spring structure to the conventional wireless suspension comprising a laminate of a spring metal such as a stainless steel foil, a plastic insulative film such as a polyimide film, and one or more sets of electrical conductors typically comprising copper traces on the insulative film spaced from the spring metal.
2. Description of the Related Art
Wireless-type disk drive suspensions integrate the load beam and flexure functions into a single laminate that is a flexure mounted to an actuator arm. Given the substantially less robust nature of the wireless laminate in comparison with the typical load beam, there is a problem with inadequate force being exerted on the slider for effective operating contact with the disk that militate against using the wireless-type suspension despite certain operating advantages and low cost.
It is an object of the invention, therefore, to provide an improved disk drive suspension of the wireless type. It is a further object to provide a wireless suspension having greater stiffness and that exerts an increased vertical force on the slider than the laminate portion alone. It is a still further object to provide a modified wireless suspension that uses the single laminate of spring metal, insulative film, and conductive traces that is cantilevered from an actuator arm, but that further includes a secondary spring structure that serves to stiffen the suspension, increase vertical force available, and define a dimple for gimballing contact with the slider.
These and other objects of the invention to become apparent hereinafter are realized in a vertical force and stiffness enhanced disk drive suspension comprising a longitudinally extended flexure having a rigid portion, a spring portion and a base portion, the base portion being adapted for mount plate-mounting of the flexure to an actuator arm, the flexure having a front face and a rear face, the flexure comprising a self-supporting laminate of a spring metal, a plastic insulative film, and plural electrically conductive traces spaced from the spring metal by the plastic insulative film, the flexure defining at its distal end a flexure tongue arranged and adapted to carry a slider at the front face of the laminate in operating proximity to a disk, the laminate providing a predetermined vertical force less than that needed for effective operation of the slider, and a secondary spring structure fixed to the laminate rear face in laminate-stiffening and laminate vertical force increasing relation sufficient for effective operation of the slider.
In this and like embodiments, typically, the secondary spring structure defines a dimple in gimballing contact with the tongue, the flexure rigid portion has opposed edge rails, the secondary spring structure has opposed edge rails at least partially between and opposite the flexure rigid portion edge rails, and, the flexure rigid portion has opposed edge rails extending toward the flexure distal end, the secondary spring structure edge rails extending closer to the flexure distal end than the flexure rigid portion edge rails.
In a further embodiment, the invention provides a vertical force and stiffness enhanced disk drive suspension comprising a longitudinally extended flexure having a rigid portion, a spring portion and a base portion, the base portion being adapted for mount plate-mounting of the flexure to an actuator arm, the flexure having a front face and a rear face, the flexure being about 1 mil in thickness and comprising a self-supporting laminate of a spring metal, a plastic insulative film, and plural electrically conductive traces spaced from the spring metal by the plastic insulative film, the flexure defining at its distal end a frame and within the frame flexure tongue arranged and adapted to carry a slider at the front face of the laminate in operating proximity to a disk, the laminate providing a predetermined vertical force less than that needed for effective operation of the slider, and a planar secondary spring structure of about 2 mils in thickness, the secondary spring structure lying parallel with and being fixed to the laminate rear face in laminate-stiffening and laminate vertical force increasing relation sufficient for effective operation of the slider.
In this and like embodiments, typically, the secondary spring structure defines a dimple in gimballing contact with the tongue, the flexure rigid portion has opposed edge rails of about 10 mils in height, the secondary spring structure has opposed edge rails of about 9 mils in height, the edge rails being at least partially between and opposite the flexure rigid portion edge rails, and the flexure rigid portion opposed edge rails have a terminus a predetermined distance from the flexure distal end, the secondary spring structure edge rails having a separate terminus a lesser predetermined distance from the flexure distal end than the flexure rigid portion edge rails.
In its method aspects, the invention provides the method of increasing the vertical force exerted against a slider by a disk drive suspension comprising a laminate of a spring metal, an insulative plastic film, and electrical conductive traces, including superimposing on the laminate a secondary spring structure adapted to stiffen the laminate in the laminate region opposite the slider.